Credit: Prof. Hezi Yizhaq/BGUSand ripples photographed on Mars by NASAs Curiosity rover in 2015 showed 2 distinct patterns– large ripples (meter scale) and a shorter “effect” ripples pattern (decimeter scale). The prevailing theory proposed since then argues that the smaller scale ripples are produced by the impact system of the particles carried by the wind like regular ripples on Earth and the larger ripples form due to hydrodynamic instability like subaqueous ripples. Credit: Prof. Hezi Yizhaq/BGUFurthermore, the global research study team has proposed an unified theoretical framework that would discuss sand ripples on Mars and on Earth. At its most fundamental level, sand ripples on Mars caused by wind appearance like sand ripples on Earth triggered by water.
Two sizes of wind-sculpted ripples are obvious in this view of the leading surface of a Martian sand dune. Dune and the smaller kind of ripples likewise exist on Earth. The larger ripples– roughly 10 feet (3 meters) apart– are a type not seen in the world. Credit: NASA/JPL-Caltech/MSSSCommon causes have the potential to overturn previous understandings.Sand ripples are fascinating. They are symmetrical yet wind, which triggers them, is extremely much not. They can be found on Mars and on Earth. They would be even more remarkable if the exact same effect found on Mars could be discovered here on Earth. What if one unified theory could discuss their development on two different worlds of our solar system?That is what Ben-Gurion University of the Negev physicist Prof. Hezi Yizhaq and Prof. Itzhak Katra and their coworkers from Denmark, Germany, Italy, China, and the United States compete in a cover short article released in Nature Geoscience.Several sizes of waves in the sand developed by the wind in the Namib Desert. You can see down the high dune small, straight waves formed in fine-grained sand and bigger mega waves covered with rough coarse sand. The coarse sand is grayish while the great sand that builds the dunes is reddish. Credit: Prof. Hezi Yizhaq/BGUSand ripples photographed on Mars by NASAs Curiosity rover in 2015 showed two unique patterns– big ripples (meter scale) and a much shorter “effect” ripples pattern (decimeter scale). The prevailing theory proposed because then argues that the smaller sized scale ripples are produced by the impact system of the particles transferred by the wind like regular ripples in the world and the bigger ripples form due to hydrodynamic instability like subaqueous ripples. It was thought that the physical conditions that produced them on Mars might not produce them on Earth.Experimental EvidenceHowever, Prof. Yizhaq and Prof. Katra have actually shown experimentally using Ben-Gurion Universitys wind tunnel and Aarhus Universitys Mars tunnel that such a phenomenon could exist on Earth– we simply havent noticed it yet because we didnt understand we ought to be looking for it.Imitating Martian sand was not simple due to the fact that its finer than sand here on Earth, discusses Prof. Yizhaq, however the development occurred when they chose to try small glass balls to represent fine grains of sand.Waves gotten in the wind tunnel of Ben Gurion University of the Negev with glass balls with a diameter of 90 microns. 2 scales of waves can be seen in the image. Small waves with a wavelength of centimeters and big waves with a wavelength of about 10 centimeters resemble waves due to the flow of water. The presence of 2 scales of waves on Mars was discovered by the Mars Curiosity Rover. Credit: Prof. Hezi Yizhaq/BGUFurthermore, the international research team has proposed a combined theoretical framework that would discuss sand ripples on Mars and on Earth. At its many fundamental level, sand ripples on Mars triggered by wind appear like sand ripples in the world triggered by water.”There is far more research study, both fieldwork and experimentally, required to show our theory, but it is amazing to propose something so radically new in a field I have actually been studying for over 20 years. It is amazing to head out and search for in the world what can clearly be seen on Mars,” says Prof. Yizhaq.The wind tunnel at Aarhus University in Denmark permits the pressure to be minimized to that on Mars, which is 200 times smaller sized than air pressure in the world. The tunnel is inside the large red tank. Credit: Prof. Hezi Yizhaq/BGUReference: “Coevolving aerodynamic and impact ripples on Earth” by Hezi Yizhaq, Katharina Tholen, Lior Saban, Nitzan Swet, Conner Lester, Simone Silvestro, Keld R. Rasmussen, Jonathan P. Merrison, Jens J. Iversen, Gabriele Franzese, Klaus Kroy, Thomas Pähtz, Orencio Durán and Itzhak Katra, 8 January 2024, Nature Geoscience.DOI: 10.1038/ s41561-023-01348-3Prof. Yizhaq is a member of the Department of Solar Energy and Environmental Physics. Prof. Itzhak Katra is a member of the Department of Environmental, Geoinformatics and Urban Planning Sciences.The research was supported by the Israel Science Foundation (Grant no. 1270/20), the German-Israel Foundation for Scientific Research and Development (GIF) (Grant no. 155-301.10/ 2018), the National Natural Science Foundation of China, Texas A&M Engineering Experiment Station, Europlanet grant no. 871149, and the Horizon 2020 Research and Innovation Program.
